Bearings are often used as critical parts in complex machines and bearing failure may lead to major damages. Replacing bearings may be complicated and results in downtime. The bearing lifetime depends strongly on the quality of the lubrication and of the seals. Monitoring the quality of the seals and of the lubrication is therefore highly desirable.
Further, it is proposed to use vibration sensors attached to rigid metallic machine parts in order to monitor the machine and to be able to stop the machine for maintenance if unexpected vibrations are detected.
The progress in mobile telecommunication technology has brought about a new generation of semiconductor-based accelerometers for use in smartphones which are highly miniaturized.